Background: Schizophrenia is a disabling illness, characterized by severe impairments in social, occupational, and community function. There is also ample evidence of significant cognitive impairments in schizophrenia, and these cognitive impairments directly relate to poorer functional outcomes. An increasing number of reviews and meta-analyses provide support for the efficacy of cognitive rehabilitation in schizophrenia, and cognitive rehabilitation services ar proliferating across the nation. In individuals with schizophrenia, the (real-world) effectiveness f this and other psychosocial treatments is diminished by lack of motivation for treatment, leading to poor treatment engagement and/or dropout. Motivational interviewing is a brief, clinically-feasible approach that has been successfully used to increase adherence to and efficacy of various treatments, and our pilot data suggest that it may also be effective in improving adherence to cognitive rehabilitation. Objectives: Our primary objective is to evaluate whether motivational enhancement can improve adherence to cognitive rehabilitation in Veterans with schizophrenia spectrum disorders. Additional objectives are to examine potential mechanisms of action (mediators) and predictors of treatment effects (moderators) associated with providing motivational enhancement for cognitive rehabilitation. Methods: One hundred twenty Veterans with schizophrenia spectrum diagnoses will be randomized to receive either brief motivational interviewing (MI) or a sham control interview (CI), both of which will be followed by 4 months of cognitive rehabilitation. Booster MI or CI sessions will be administered monthly over the course of the cognitive rehabilitation. Comprehensive assessments will be conducted at baseline and end of cognitive rehabilitation, with additional assessments of task-specific intrinsic motivation, cognitive training task performance, cognition and functional ability at key points throughout the study. Significance: Improving adherence to cognitive rehabilitation can lead to enhanced cognitive function, which would in turn allow individuals to better take advantage of other psychosocial treatments, resulting in better community functioning. The proposed project will advance a line of research aimed at increasing the efficacy and effectiveness of psychosocial treatments in decreasing disability, improving community function, and promoting social integration in Veterans diagnosed with psychotic disorders. If found efficacious, brief motivational interviewing could also be adapted to enhance adherence to other forms of rehabilitation in Veterans with psychosis or other serious mental illnesses.